Mania reduces perceived pain intensity in patients with chronic pain: preliminary evidence from retrospective archival data.

OBJECTIVE Bipolar disorder is associated with poor pain outcomes, but the extant literature has not taken into account how mania or hypomania - a central feature of bipolar disorders - influences pain intensity. The objective of this study was to describe whether patients recalled experiencing reduced pain intensity during manic or hypomanic episodes. DESIGN AND SETTING This study used a retrospective design using archival data from patient's medical records. SUBJECTS A total of 201 patients with chronic pain with bipolar I (39.6%) or bipolar II (60.4%) disorder who were undergoing a psychological evaluation for an interventional pain procedure were included in this study. METHODS Patients underwent a semistructured interview where they were asked if they recalled reductions in pain intensity during their most recent manic or hypomanic episode. The proportion of patients who responded "yes" versus "no" to this question was the primary outcome variable. RESULTS Results reveal that 64.2% of patients recalled experiencing a reduction in pain intensity during their most recent manic or hypomanic episode. CONCLUSION Perceptions of reduced pain intensity during mania or hypomania may contribute to a cycle of increased activity during manic episodes, which may increase pain over time. It may also lead to false-positive findings on spinal cord stimulator trials and diagnostic pain blocks, among other interventional pain procedures. The preliminary findings of this study highlight the clinical importance of assessing for bipolar disorders in patients with chronic pain.